1. Field of the Invention
The present invention relates to a computer controlled communication system according to the preamble to claim 1.
2. Discussion of Background Information
Modern telephone systems, in particular ISDN communication systems, permit the user to employ various services (e.g. phone, teletex, fax, videotex, and data transmission). The integration of these services has lead to the development of devices, which give the user access to various services. A multi-functional terminal for vocal, text, image, and data communication is described in K. P. Mellwig and W. Wilde, Das universelle Multidevice HICOM 3510, ISDN im Bxc3xcro [The Universal HICOM 3510 Multi-device, ISDN in the Office], Siemens AG, Mxc3xcnchen 1985, ISBN 3-8009-3846-4, pp. 44-49. Terminals of this type are normally not suited to replace a personal computer (PC below), of the kind currently employed for complex uses in the office (e.g. user-friendly word processing systems or high-performance graphics and database systems). Communication devices in the office are therefore often used independently of the data devices. Occasionally, PCs are also connected to private branch exchanges via special interface subassemblies. The large expenditure required for equipping all PCs with corresponding interface subassemblies is disadvantageous. Furthermore, the communication device connected to the PC is not operational when the PC is switched off.
Therefore in WO 94/21901, the systems provided for data processing are integrated into an intelligent telephone system. This telephone system is directly connected to the telephones for which no multiple functions are required and which also remain operational when the integrated EDV system is not in operation. The telephone system is connected to a network (LAN) via an integration element, which contains a computer and an ISDN interface subassembly among other things, to which network a network server and a number of PCs are connected. As soon as a device is called, the integration element and the network produce a connection to a PC, which is associated with the device that has been called. For example, all existing data regarding the calling party is transmitted from the computer of the integration element to the PC and is displayed there.
In this embodiment, it is disadvantageous that a computer (integration element) must be connected between the telephone system and the network, which element accesses the PCs, which are connected to the network, in parallel fashion or via the network server already provided. Technical communication functions selected on the PC (broker""s call, conference call, etc.) must be respectively transmitted via the integration element to the telephone system and executed there. The integration element or the computer must undergo maintenance just like the network server. Furthermore with software adaptations, attention must be respectively paid that the compatibility between the integration element and the network server is maintained. The system disclosed in WO 94/21091 is therefore relatively complex. When problems arise, the telephone system, the devices, the integration element, the network server, and the PCs, as well as the connecting lines associated with them must be checked. The maintenance of data and programs has to be carried out for both the integration element and the network server.
The object of the present invention, therefore, is to produce an easily maintainable computer controlled communication system at a low cost and using existing resources, which permits the interaction of telephone devices and associated PCs.
This object is attained by the measures disclosed in the characterizing part of claim 1. Advantageous embodiments of the invention are disclosed in the other claims.
The invention is based on the knowledge that the prior art of modern network embodiments permits the solution of existing communication problems. The EDV systems are therefore not integrated into a communication system. In lieu of these, the EDV system is expanded by the necessary technical communication performance characteristics. As a result, the structure of the communication system is greatly simplified in comparison to the known embodiments (WO 94/21091). An integration element between the telephone system and the network (LAN) or the network server is no longer necessary. An existing network with a network server and PCs can be expanded into a communication system according to the invention at a low cost.